Search systems and methods using enhanced contextual queries

ABSTRACT

Systems and methods are provided for implementing searches using contextual information associated with a Web page (or other document) that a user is viewing when a query is entered. The page includes a contextual search interface that has an associated context vector representing content of the page. When the user submits a search query via the contextual search interface, the query and the context vector are both provided to the query processor and used in responding to the query. The context vector can be enhanced by the addition of terms related to one or more terms appearing in the context vector or the query.

CROSS-REFERENCES TO RELATED APPLICATIONS

The present disclosure is related to the following commonly-assigned co-pending U.S. patent applications:

-   -   application Ser. No. 11/033,417, filed Jan. 10, 2005, entitled         “User Interfaces for Search Systems Using In-Line Contextual         Queries”;     -   application Ser. No. 11/033,101, filed Jan. 10, 2005, entitled         “User Interface Tool for Text Selection”;     -   application Ser. No. 10/713,576, filed Nov. 12, 2003, entitled         “Systems and Methods for Generating Concept Networks from User         Queries.”     -   application Ser. No. 10/797,614, filed Mar. 9, 2004, entitled         “Systems and Methods for Search Processing Using Superunits.”     -   The respective disclosures of these applications are         incorporated herein by reference for all purposes.

BACKGROUND OF THE INVENTION

The present invention relates in general to search systems and methods and in particular to search systems and methods using in-line contextual queries.

The World Wide Web (Web), as its name suggests, is a decentralized global collection of interlinked information—generally in the form of “pages” that may contain text, images, and/or media content—related to virtually every topic imaginable. A user who knows or finds a uniform resource locator (URL) for a page can provide that URL to a Web client (generally referred to as a browser) and view the page almost instantly. Since Web pages typically include links (also referred to as “hyperlinks”) to other pages, finding URLs is generally not difficult.

What is difficult for most users is finding URLs for pages that are of interest to them. The sheer volume of content available on the Web has turned the task of finding a page relevant to a particular interest into what may be the ultimate needle-in-a-haystack problem. To address this problem, an industry of search providers (e.g., Yahoo!, MSN, Google) has evolved. A search provider typically maintains a database of Web pages in which the URL of each page is associated with information (e.g., keywords, category data, etc.) reflecting its content. The search provider also maintains a search server that hosts a search page (or site) on the Web. The search page provides a form into which a user can enter a query that usually includes one or more terms indicative of the user's interest. Once a query is entered, the search server accesses the database and generates a list of “hits,” typically URLs for pages whose content matches keywords derived from the user's query. This list is provided to the user. Since queries can often return hundreds, thousands, or in some cases millions of hits, search providers have developed sophisticated algorithms for ranking the hits (i.e., determining an order for displaying hits to the user) such that the pages most relevant to a given query are likely to appear near the top of the list. Typical ranking algorithms take into account not only the keywords and their frequency of occurrence but also other information such as the number of other pages that link to the hit page, popularity of the hit page among users, and so on.

To further facilitate use of their services, some search providers now offer “search toolbar” add-ons for Web browser programs. A search toolbar typically provides a text box into which the user can type a query and a “Submit” button for submitting the query to the search provider's server. Once installed by the user, the search toolbar is generally visible no matter what page the user is viewing, enabling the user to enter a query at any time without first navigating to the search provider's Web site. Searches initiated via the toolbar are processed in the same way as searches initiated at the provider's site; the only difference is that the user is spared the step of navigating to the search provider's site.

While automated search technologies can be very helpful, they do have a number of limitations, a primary one being that users struggle to convey enough contextual information to direct the search to relevant content. An overly broad query (too little context) can return a few needles of relevant content buried in a haystack of irrelevant hits; an overly narrow query (too much context) may result in filtering out the needles along with the hay. Often a user has a fairly specific context in mind, but this specific context may not be reflected in a query. For example, a user who enters the query “jaguar” might be thinking of the automobile, the animal, the professional football team, or something else entirely.

In principle, contextual information might be gleaned from what the user was doing prior to entering the query. It is well known that users are often inspired to conduct searches when information they are currently reviewing raises a further question. For example, a user who enters the query “jaguar” after (or while) viewing an automobile-related page is most likely interested in the automobile while one who enters the same query after (or while) viewing a page about zoos is most likely interested in the animal. Existing search technologies do not provide reliable ways of gathering such contextual information or using it to respond to a query.

Therefore, it would be desirable to provide a search server with contextual information that is usable for responding to queries.

BRIEF SUMMARY OF THE INVENTION

Embodiments of the present invention provide systems and methods for implementing searches using contextual information associated with a page or other document that a user is viewing when a query is entered. In some embodiments, the page or document includes a contextual search interface that has an associated context vector representing content of the page or document. When the user submits a search query via the contextual search interface, the context vector is also provided to the query processor and used in responding to the query. Context vectors may also be used in other ways, such as selecting additional content that may be of interest to a user.

According to one aspect of the present invention, a method for processing a query is provided. Via a contextual search interface, a user query is received; the user query includes a first query term supplied by a user. A context vector associated with the contextual search interface is also received; the context vector includes a first context term extracted from content associated with the contextual search interface. The context vector is enhanced with at least one additional term related to at least one of the first query term or the first context term. A search corpus is searched using the user query and the enhanced context vector to obtain a search result including a list of hits. The search result is transmitted for presentation to the user.

In some embodiments, the additional term may be related to the query term; in other embodiments, the additional term may be related to the context term. For instance, enhancing the context vector may include retrieving from a concept network a plurality of terms having a semantic relationship to at least one of the first query term or the first context term, and selecting at least one of the retrieved terms as the at least one additional term.

According to another aspect of the present invention, a method for processing a query is provided. A user query that includes an ambiguous query term is received. A number of meanings for the ambiguous query term are identified. A user prompt for selection of one of the meanings is transmitted, and a user selection of one of the meanings is received. A context vector corresponding to the selected meaning is defined, the context vector including at least one term. A search corpus is searched using the user query and the context vector to obtain a search result including a list of hits. The search result is transmitted for presentation to the user.

In some embodiments, identifying meanings includes retrieving from a concept network a number of alternative categories to which the ambiguous query term belongs, wherein each of the alternative categories corresponds to a different one of the meanings. In other embodiments, identifying meanings includes retrieving from a concept network a number of alternative definitions for the ambiguous query term.

In some embodiments, defining the context vector includes retrieving from a concept network a number of terms related to the ambiguous query term, wherein each related term is related to the selected meaning of the ambiguous query term; and selecting at least one of the related terms for inclusion in the context vector. The related terms may include, for example, a synonym of the ambiguous query term, a category of which the ambiguous query term is a member, a sub-category subsumed by the ambiguous query term, and so on.

In some embodiments, the user query may further include a user context vector, and the defined context vector may include at least one term from the user context vector.

According to yet another aspect of the present invention, a system for processing a query includes an input module, an enhancement module, a search module, and an output module. The input module is configured to receive a search query that includes a query term entered by a user via a contextual search interface and a context vector associated with the contextual search interface, the context vector including at least one context term representative of content associated with the contextual search interface. The enhancement module is configured to add an additional term to the context vector, where the additional term is related to one or more of the query term or the at least one context term. The search module is configured to search a search corpus using the user query and the enhanced context vector and to provide a search result including a list of hits. The output module is configured to transmit the search result for presentation to the user.

The following detailed description together with the accompanying drawings will provide a better understanding of the nature and advantages of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a high-level block diagram of an information retrieval and communication network including a client system according to an embodiment of the present invention.

FIG. 2 is a block diagram of another information retrieval and communication network according to an embodiment of the invention.

FIG. 3 is an illustration of a Web page with a contextual search interface according to an embodiment of the present invention.

FIG. 4 is an illustration of a context vector for a contextual search according to an embodiment of the present invention.

FIG. 5 is an illustration of a Web page with a contextual search interface in an inactive state according to an embodiment of the present invention.

FIG. 6 is an illustration of a Web page with multiple contextual search interfaces according to an embodiment of the present invention.

FIG. 7 is a simplified block diagram of a context vector server system according to an embodiment of the present invention.

FIG. 8 is a flow diagram of a process performed by a content developer for creating a contextual search interface according to an embodiment of the present invention.

FIGS. 9A-9B are flow diagrams of processes for generating a context vector according to embodiments of the present invention.

FIG. 10 is a flow diagram of a process for user creation of a contextual search interface according to an embodiment of the present invention.

FIG. 11 is a flow diagram of a third process for generating a context vector according to an embodiment of the present invention.

FIG. 12 is a flow diagram of a process for executing a contextual search according to an embodiment of the present invention.

FIG. 13 is a flow diagram of another process for executing a contextual search according to an embodiment of the present invention.

FIG. 14 is a flow diagram of a process for performing a contextual search with an enhanced context vector according to an embodiment of the present invention.

FIG. 15 is a flow diagram of a process for generating an enhanced context vector according to an embodiment of the present invention.

FIG. 16 illustrates a search results page with a user-editable context vector according to an embodiment of the present invention.

FIG. 17 is a flow diagram of a process for disambiguation of a query according to an embodiment of the present invention.

FIG. 18 is a flow diagram of a process for detecting and resolving ambiguity in a contextual search according to an embodiment of the present invention.

FIG. 19 is an illustration of a Web page with contextual search interfaces including augmented content according to an embodiment of the present invention.

FIG. 20 is a flow diagram of a process for selecting augmented content according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION I. Overview

A. Network Implementation

FIG. 1 illustrates a general overview of an information retrieval and communication network 10 including a client system 20 according to an embodiment of the present invention. In computer network 10, client system 20 is coupled through the Internet 40, or other communication network, e.g., over any local area network (LAN) or wide area network (WAN) connection, to any number of server systems 501 to 50N. As will be described herein, client system 20 is configured according to the present invention to communicate with any of server systems 501 to 50N, e.g., to access, receive, retrieve and display media content and other information such as web pages.

Several elements in the system shown in FIG. 1 include conventional, well-known elements that need not be explained in detail here. For example, client system 20 could include a desktop personal computer, workstation, laptop, personal digital assistant (PDA), cell phone, or any WAP-enabled device or any other computing device capable of interfacing directly or indirectly to the Internet. Client system 20 typically runs a browsing program, such as Microsoft's Internet Explorer™ browser, Netscape Navigator™ browser, Mozilla™ browser, Opera™ browser, or a WAP-enabled browser in the case of a cell phone, PDA or other wireless device, or the like, allowing a user of client system 20 to access, process and view information and pages available to it from server systems 501 to 50N over Internet 40. Client system 20 also typically includes one or more user interface devices 22, such as a keyboard, a mouse, touch screen, pen or the like, for interacting with a graphical user interface (GUI) provided by the browser on a display (e.g., monitor screen, LCD display, etc.), in conjunction with pages, forms and other information provided by server systems 501 to 50N or other servers. The present invention is suitable for use with the Internet, which refers to a specific global internetwork of networks. However, it should be understood that other networks can be used instead of or in addition to the Internet, such as an intranet, an extranet, a virtual private network (VPN), a non-TCP/IP based network, any LAN or WAN or the like.

According to one embodiment, client system 20 and all of its components are operator configurable using an application including computer code run using a central processing unit such as an Intel Pentium™ processor, AMD Athlon™ processor, or the like or multiple processors. Computer code for operating and configuring client system 20 to communicate, process and display data and media content as described herein is preferably downloaded and stored on a hard disk, but the entire program code, or portions thereof, may also be stored in any other volatile or non-volatile memory medium or device as is well known, such as a ROM or RAM, or provided on any media capable of storing program code, such as a compact disk (CD) medium, a digital versatile disk (DVD) medium, a floppy disk, and the like. Additionally, the entire program code, or portions thereof, may be transmitted and downloaded from a software source, e.g., from one of server systems 501 to 50N to client system 20 over the Internet, or transmitted over any other network connection (e.g., extranet, VPN, LAN, or other conventional networks) using any communication medium and protocols (e.g., TCP/IP, HTTP, HTTPS, Ethernet, or other conventional media and protocols).

It should be appreciated that computer code for implementing aspects of the present invention can be C, C++, HTML, XML, Java, JavaScript, etc. code, or any other suitable scripting language (e.g., VBScript), or any other suitable programming language that can be executed on client system 20 or compiled to execute on client system 20. In some embodiments, no code is downloaded to client system 20, and needed code is executed by a server, or code already present at client system 20 is executed.

B. Search System

FIG. 2 illustrates another information retrieval and communication network 110 for communicating media content according to an embodiment of the invention. As shown, network 110 includes client system 120, one or more content server systems 150, and a search server system 160. In network 110, client system 120 is communicably coupled through Internet 140 or other communication network to server systems 150 and 160. As discussed above, client system 120 and its components are configured to communicate with server systems 150 and 160 and other server systems over Internet 140 or other communication networks.

1. Client System

According to one embodiment, a client application (represented as module 125) executing on client system 120 includes instructions for controlling client system 120 and its components to communicate with server systems 150 and 160 and to process and display data content received therefrom. Client application 125 may be transmitted and downloaded to client system 120 from a software source such as a remote server system (e.g., server systems 150, server system 160 or other remote server system), or client application module 125 may also be provided on any software storage medium (floppy disk, CD, DVD, etc.) that is readable by client system 120 as discussed above. For example, in one aspect, client application 125 may be provided over Internet 140 to client system 120 in an HTML wrapper including various controls such as, for example, embedded JavaScript or Active X controls, for manipulating data and rendering data in various objects, frames and windows.

Client application module 125 advantageously includes various software modules for processing data and media content. In one embodiment, these modules include a specialized search module 126, a user interface module 127, and an application interface module 128. Specialized search module 126 is configured for processing search requests (also referred to herein as queries) to be sent to search server 160 and search result data received from search server 160. Specific aspects of specialized search module 126 are described below.

User interface module 127 is configured for rendering data and media content in text and data frames and active windows, e.g., browser windows and dialog boxes. In some embodiments, user interface module 127 includes or communicates with a browser program, which may be a default browser configured on client system 120 or a different browser. Application interface module 128 is configured to support interfacing and communicating between client application 125 and various other applications executing on client 120, such as e-mail applications, instant messaging (IM) applications, browser applications, document management applications and others.

User interface module 127 advantageously provides user input interfaces allowing the user to enter queries for processing by search server system 160. For example, where user interface module 127 includes or communicates with a browser, the user may be able to enter a URL or activate a control button to direct the browser to a Web search page (or site) from which the user can submit a query to search server system 160 for processing. In addition or instead, user interface module 127 may include a search toolbar or other interface via which the user can enter and submit a query without first navigating to the search page. Queries entered using user interface module 127 may be preprocessed by specialized search module 126 prior to being sent to search server system 160, e.g., to remove so-called “stop words” (“the,” “and,” etc.), to correct spelling errors, or the like.

In accordance with an embodiment of the present invention, client application 125 may include various features for adding context data (referred to herein as a “context vector”) to the user's queries. For example, specialized search module 126 may be configured to generate context vectors based on content the user is currently viewing at the time a query is entered. As another example, in some embodiments of the present invention, Web pages displayed in the browser may include one or more context vectors that can be used to supplement user-entered queries. User interface module 127 may be configured to detect such contextual vectors in a page being displayed and use context vector data to supplement a query entered by the user. These and other features are described further below.

2. Search Server System

According to one embodiment of the invention, search server system 160 is configured to provide search result data and media content to client system 120, and content server system 150 is configured to provide data and media content such as web pages to client system 120, for example, in response to links selected by the user in search result pages provided by search server system 160. In some variations, search server system 160 returns content as well as, or instead of, links and/or other references to content.

Search server system 160 references various page indexes 170 that are populated with, e.g., pages, links to pages, data representing the content of indexed pages, etc. Page indexes may be generated by various collection technologies such as an automatic web crawler 172; in addition, manual or semi-automatic classification algorithms and interfaces may be provided for classifying and ranking web pages within a hierarchical category structure. Such technologies and algorithms may be of generally conventional design, and a detailed description is omitted as not being critical to the present invention.

In one embodiment, an entry in page index 170 includes a search term, a reference (e.g., a URL or other encoded identifier) to a page in which that term appears and a context identifier for the page. The context identifier may be used for grouping similar results for search terms that may have different meanings in different contexts. For example, the search term “jaguar” may refer to the British automobile, to an animal, to a professional football team, and so on. The context identifier for a page can be used to indicate which of these contexts is applicable. In one embodiment, the context identifier includes a category for the page, with the category being assigned from a predefined hierarchical taxonomy of content categories. A page reference may be associated with multiple context identifiers, so the same page (or a link thereto) may be displayed in multiple contexts. In some embodiments, context identifiers are automatically associated with page links by the system as users perform various searches; the identifiers may also be modified and associated with links manually by a team of one or more index editors.

Search server system 160 is configured to provide data responsive to various search requests received from a client system 120, in particular from search module 126 and/or user interface module 127. For example, search server system 160 may include a query response module 164 that is configured with search related algorithms for identifying and ranking Web pages relative to a given query, e.g., based on a combination of logical relevance (which may be measured by patterns of occurrence of search terms in the query), context identifiers, page sponsorship, etc.

In accordance with an embodiment of the present invention, query response module 164 is also configured to receive and make use of context vector data that may be provided in association with a query in order to further enhance the response to queries. Use of context vector data in responding to queries is described further below. Query response module 164 may also enhance search result information with additional information (e.g., links and/or advertising copy) obtained from a sponsored content database 162. Sponsored content database 162 may be implemented as part of page index 170 by the inclusion of additional fields in each entry to identify page references that are sponsored and keywords for triggering the display of sponsored content, or it may be implemented in a separate database.

In some embodiments, search server 160 also includes a context processing module 166 that is configured with various algorithms for processing received content to generate a context vector representative of the received content. In general, a context vector may include any data that represents all or part of the content. For example, one embodiment of a context vector for text content may include keywords such as terms (e.g., words or phrases) that appear in the content, and each such term may have an associated frequency count reflecting how many times that term occurs in the content. Other types of data may also be included, e.g., URLs or other data identifying any links that may be included in the content, the URL or other identifier of the page that contains the content, category data associated with the content or with a page that contains the content, and so on. In some embodiments, context processing module 166 also has access to a concept network (not explicitly shown) that represents semantic and/or logical relationships among various words and phrases. Terms appearing in received content or queries can be used to obtain related terms from the concept network, and the related terms can be used to enhance a context vector. Examples of such enhancement are described below.

In some embodiments, a content augmentation server 180 is also provided. Content augmentation server 180 communicates via Internet 140 with client application 125 to enhance the content of a Web page being displayed with “special content” that is advantageously selected based on context vector data associated with the displayed page. In circumstances where the user has indicated an interest in information related to a particular context (examples are described below), client application 125 transmits a context vector to content augmentation server 180, and content augmentation server 180 responds with special content to be added to a Web page being displayed by client application 125.

In one embodiment, content augmentation server 180 and search server 160 are under common control, and content augmentation server 180 advantageously selects special content from sponsored content database 162. In another embodiment, content augmentation server 180 may be independent of search server 160 and may have its own database of special content from which selections can be made based on context vectors provided by client application 125.

It will be appreciated that the search system described herein is illustrative and that variations and modifications are possible. The content server, search server, and content augmentation server systems may be part of a single organization, e.g., a distributed server system such as that provided to users by Yahoo! Inc., or they may be part of disparate organizations. Each server system generally includes at least one server and an associated database system, and may include multiple servers and associated database systems, and although shown as a single block, may be geographically distributed. For example, all servers of a search server system may be located in close proximity to one another (e.g., in a server farm located in a single building or campus), or they may be distributed at locations remote from one another (e.g., one or more servers located in city A and one or more servers located in city B). Thus, as used herein, a “server system” typically includes one or more logically and/or physically connected servers distributed locally or across one or more geographic locations; the terms “server” and “server system” are used interchangeably.

The search server system may be configured with one or more page indexes and algorithms for accessing the page index(es) and providing search results to users in response to search queries received from client systems. The search server system might generate the page indexes itself, receive page indexes from another source (e.g., a separate server system), or receive page indexes from another source and perform further processing thereof (e.g., addition or updating of the context identifiers).

C. Contextual Search Interface

As mentioned above, user interface module 127 of client application 125 generally includes one or more interfaces enabling the user to submit queries to search server 160, e.g., by navigating a browser to a search page hosted by search server 160 or by providing a toolbar interface for query submission. Such interfaces may be implemented in a generally conventional fashion.

In accordance with an embodiment of the present invention, in addition to (or instead of) such interfaces, users may also enter contextual queries using a “contextual search” interface that may be implemented as a visible element on any “hosting” Web page. (As used herein, the term “hosting Web page,” or “hosting page,” is to be understood as referring to any page that includes at least one contextual search interface; hosting pages might or might not be under common control with search server 160 or content augmentation server 180.) Each contextual search interface has a context vector associated with it. The context vector, which need not be visible on the hosting page, provides additional data reflecting the content of the hosting page (or a portion thereof). This data can be used e.g., by query response module 164, during query processing as described below.

An example of a contextual search interface will now be described. FIG. 3 shows a hosting page 300 that has some content 302, as it might appear when displayed on client system 120 of FIG. 2. Hosting page 300 includes a contextual search interface 304 that is advantageously placed near content 302. A user may initiate a contextual search by entering a query (e.g., “fuel consumption”) into a text field 306 of interface 304 and activating a “submit” control 308, which may be, e.g., a clickable button. The source code (not shown) for hosting page 300 includes a context vector associated with contextual search interface 304. In this embodiment, the context vector is not actually displayed in page 300, although its data is included with the source code provided to client application 125 when page 300 is requested.

The context vector, which may be implemented in various ways, advantageously includes one or more terms and/or category labels (or any other data) representative of the neighboring content 302. FIG. 4 is an example of a context vector 400 that might be provided for a search initiated from contextual search interface 304 of FIG. 3. Context vector 400 includes a list of terms 402 (“cabrio,” “golf,” etc.) that appear in content 302 and additional information associated with each term. In this example, the additional information includes a term frequency 404, a document frequency 406, a weight 408, and a term type 410. Term frequency 404 reflects the number of times the term occurs in content 302. Document frequency 406 reflects the number of documents in the search corpus that contain the term. Weight 408 reflects an importance assigned to the term and may be computed from information such as whether the term occurs in text or in headings, the term frequency 404, and/or the document frequency 406. Term type 410 can be used to distinguish different types of data that may be included in the context vector, e.g., terms from the text, category data, URL data, and so on. It is to be understood that a context vector may also include more, fewer, or different elements from those shown in FIG. 4, and the elements may be provided in any desired format. In one embodiment, context vector 400 is included in the source code for hosting page 300 in association with the code for contextual search interface 304.

When a user using client application 125 (of FIG. 2) to view hosting page 300 initiates a search by entering a query into text field 306 and activating submit control 308, the query that is sent by client application 125 to search server 160 for processing advantageously includes not only the explicit user input from text field 306 but also a representation of context vector 400. For example, in one implementation of contextual search interface 304, Web page 300 includes program code for sending an HTTP (hypertext transport protocol) request to search server 160 in response to submit control 308. This program code can include code for appending the user's query and a representation of the context vector as additional data to the URL used for the HTTP request.

In addition to the user's query (from text field 306) and context vector 400, search server 160 may also receive other metadata, such as an identifier of the user (if known), the user's IP address, the time of day, and so on. This metadata, which might or might not be specific to the hosting page or the contextual search interface, may be obtained from client application 125 or from other sources.

Upon receiving a query initiated through contextual search interface 304, search server 160 uses query response module 164 to execute a search based on the user's query and the context vector (and optionally any other available metadata). Query response module 164 generates and ranks a list of hits. The resulting list of hits, which generally depends at least in part on the context vector, is returned to the user, e.g., in the form of a search results page. In executing the search, the context vector may be used in various ways. For instance, in one embodiment, the user's query (e.g., the explicit input in text field 306 in FIG. 3) is modified by adding one or more keywords selected from the context vector; in another embodiment, the search is executed using the user's query as submitted, with keywords and/or category data from the context vector used in ranking the results. Additional embodiments are described below.

In some embodiments, contextual search interfaces for a hosting page may be initially displayed in an “inactive” state in which only a relatively small icon appears on the page. An example of an inactive contextual search interface is illustrated in FIG. 5. Hosting page 300′ is generated from the same source code as hosting page 300 of FIG. 3 and has the same content 302. In page 300′, however, only a small contextual search icon 504 is displayed, rather than the full contextual search interface 304 shown in FIG. 3. Icon 504 represents an inactive contextual search interface; a user viewing page 300′ who desires to perform a contextual search related to content 302 can activate the contextual search interface, e.g., by clicking on or otherwise selecting icon 504. Selecting icon 504 causes page 300 of FIG. 3, with the active contextual search interface 304, to be displayed so that the user can perform a contextual search.

Any number of contextual search interfaces may be provided on a hosting page, and each contextual search interface may have its own context vector that reflects the nearby content. For example, FIG. 6 shows a hosting page 600 whose content includes several summaries 602, 604, 606 of different news stories. Each summary 602, 604, 606 has a respective contextual search icon 612, 614, 616 placed near it. Each icon 612, 614, 616 is the inactive state of a different contextual search interface, each of which has its own context vector derived from the adjacent summary 602, 604, 606. Any one of these icons can be activated by a user and then used to initiate a contextual search (e.g., in the same manner as described above with reference to icon 504 and active contextual search interface 304). The context vector for a search initiated from icon 612 is advantageously derived from summary 602 while the context vector for a search initiated from icon 614 is advantageously derived from summary 604 and so on. Since icons 612 and 614 have different associated context vectors, the search results (the hits or their ranking or both) will generally differ for searches initiated via icons 612 and 614, even if the same query is entered.

In one embodiment, described further below, the creator of a hosting page may determine how many contextual search interfaces to include on the page, where they are to be located, and which portion(s) of the page should be used to define the context for the search.

It is to be understood that the contextual search interface shown herein is illustrative and that variations and modifications are possible. Further examples of contextual search interfaces that may be used in connection with the present invention are described in above-referenced application Ser. No. 11/033,417.

The following sections describe example embodiments for creation of contextual search interfaces and context vectors (Section II), use of context vectors in processing queries (Section III), and additional optional features for further enhancing contextual searches (Sections IV and V).

II. Creation of Contextual Search Interfaces and Context Vectors

Contextual search interfaces and context vectors can be created in advance of a contextual search operation, e.g., under control of a content developer, or at the time of a contextual search operation, e.g., under user control. In the embodiment of FIG. 2, context processing module 166 provides services for creating context vectors on demand in response to requests from various client programs, including content development clients and/or Web browser clients executing on client system 120.

Creation of contextual search interfaces will now be described with reference to FIG. 7, a simplified block diagram of a context vector server system 700 according to an embodiment of the present invention. A context module 702 communicates with a context client 704, e.g., via the Internet. Context module 702 advantageously corresponds to context processing module 166 of FIG. 2 and may be implemented as a component of search server 160 as shown in FIG. 2 or in a separate computer system. Context client 704 may be, e.g., a content development program that is capable of adding contextual search interfaces to page content, or a browser program that is capable of initiating a contextual search.

Context module 702 communicates with a number of dictionaries that may be implemented in one or more databases or other data stores of generally conventional design. As used herein, “dictionary” refers generally to any data store in which information related to a word or phrase is retrievable by a lookup operation using the word or phrase as an index; a dictionary is not limited to any particular information content and might or might not provide an exhaustive list of words and/or phrases.

In system 700 four dictionaries are provided. Term dictionary 706 includes a list of terms (which may include single words and/or phrases) derived from a search corpus (e.g., as represented in page index 170 of FIG. 2). Each term in term dictionary 706 is advantageously associated with a “document frequency” that reflects the number (or fraction) of documents in the search corpus that include at least one occurrence of that term.

Segment dictionary 708 includes phrases (“segments”) extracted from documents in the search corpus. Each segment in dictionary 708 represents a group of contiguous words found in the same arrangement in at least a minimum number (or fraction) of documents in the search corpus. A document frequency is advantageously stored in association with each segment in segment dictionary 708.

Concept network 710 is a representation of units and relationships among units. Specific examples of concept network 710 and its use in forming enhanced context vectors are described in Section III.B below.

Stopword dictionary 712 includes words that occur so frequently as to be meaningless for purposes of selecting documents. Examples include articles (“a”, “the”, etc.); conjunctions (“and”, “but”); prepositions (“to”, “on”, “in”); and so on. As described below, stopword dictionary 712 is advantageously used to exclude words from a context vector.

It is to be understood that the specific combination of dictionaries described herein is illustrative and that other combinations may be used.

In operation, context client 704 transmits text (and optionally one or more query terms) to context module 702. Context module 702 may use any combination of dictionaries 706, 708, 710, 712 (or other dictionaries) for generating context vectors; specific examples of algorithms that can be employed are described below. Once the context vector is generated, context module 702 may return it to context client 704 or provide it directly to search server 160 for use in query processing.

A. By Content Providers

In some embodiments, one or more contextual search interfaces can be added to a Web page at the discretion of a content developer that creates the Web page. For example, a search provider (or other promulgator of contextual search technologies) may publish an application program interface (API) for implementing contextual searches. The API includes a format for specifying contextual search requests so that such requests can be recognized and processed by search server 160. In one embodiment, the API specifies a base URL for submitting contextual searches to search server 160 and a format for enhancing the base URL with additional data representing the user's query and the context vector. The API may also specify formats for encoding the query and/or context vector as appropriate to a particular implementation.

In some embodiments, the API may also specify the appearance and/or features of the contextual search interface. For example, the API might specify whether the interface should initially be displayed as an inactive-state icon, what such an icon should look like, and a standard phrase to be displayed with the icon to alert users to the opportunity for performing a contextual search. Other aspects of the API might specify features of the contextual search interface in its active state, such as whether a text box and/or other input fields are to be provided and what such fields should look like. While optional, providing uniform specifications for the esthetic aspects of contextual search may assist in promoting user awareness and recognition of contextual search interfaces.

All or part of the API may be provided by making available images that can be inserted into the Web page or suitable code blocks in commonly used Web page coding languages (such as HTML) that content creators can simply insert into their pages.

The content provider can implement a contextual search interface by including appropriate code in the source code for the hosting page and supplementing this code with appropriate data for a context vector representing the actual content of the hosting page. Any code in any language may be used, as long as execution of the code results in contextual search requests, in the API-compliant format, being generated and submitted to search server 160 in response to input to the contextual search interface.

In other embodiments, the search provider (or other promulgator of contextual search technologies) further facilitates creation of contextual search interfaces by content providers, e.g., by automating the generation of some or all of the contextual search code for a hosting page. As one example, generation of context vectors from hosting page content may advantageously be automated using context module 702 of FIG. 7. In this instance, a content development client 704 provides text to context module 702 and receives properly formatted contextual search code, including the context vector, in response.

FIGS. 8 and 9A-9B are flow diagrams illustrating a partially automated process for creating a contextual search interface, with FIG. 8 showing a process 800 performed by the content developer using client 704 of FIG. 7 and FIGS. 9A-9B showing alternative processes 900 that may be performed by context module 702.

Process 800 begins with the content developer creating or modifying content for a Web page (step 802) that is to include a conceptual search interface. The content may be created using any manual or automatic technique, including the use of conventional Web development software. At some point, the content developer determines that it would be desirable to have a contextual search interface associated with some portion (or all) of the hosting Web page's content. The content developer selects the content that is to be associated with the contextual search interface (step 804) and submits it to the context vector server (step 806).

Submission of content to the context vector server may be done in a number of ways. In some embodiments the search provider offers a Web-browser-based context analysis interface for content providers. This interface may be, e.g., an interface to context module 702 shown in FIG. 7. The content developer may navigate his own browser to this interface and enter (e.g., by copying and pasting) appropriate content from the hosting page. In other embodiments, the content developer may navigate a browser to the search provider's context analysis interface and submit a URL for the hosting Web page. In still other embodiments, the search provider may distribute a software tool (e.g., incorporating aspects of algorithms shown in FIGS. 9A-9B) that the content provider can use to select content and submit it to the search provider without using a Web browser. This tool may take various forms, such as a desktop tool or a widget that can be integrated into various Web content development software programs.

Upon receiving content from a developer, context module 702 analyzes the content and generates a context vector. FIG. 9A is a flow diagram of a process 900 that may be, implemented in context module 702. Process 900 begins when content to be associated with a contextual search interface is received by context module 702 (step 902). The text may be received in, or converted to, a conventional encoding such as UTF-8.

At step 904, the received content is tokenized. Tokenizing may be done using conventional techniques and may include, e.g., detecting word boundaries (which may be based on Unicode or other conventional techniques), canonicalizing words (e.g., removing suffixes, correcting spelling errors or variants, and the like), eliminating various words that are too common to be helpful in searches (e.g., “the,” “and”), and so on. At step 906, the tokens are sorted according to suitable criteria, such as frequency of occurrence of the term in the content, and at step 908 the most frequently occurring tokens are selected for inclusion in the context vector. The number of tokens selected may be limited, e.g., to some integer K.

At step 910, a context vector is created using the tokens. In one embodiment, the context vector includes the selected tokens as well as their respective frequencies and other optional information. In some embodiments, co-occurrences and correlations between tokens are also used to identify phrases that can also be incorporated into the context vector. (For instance, in content 302 of FIG. 3, the phrase “Golf Cabrio” might be identified.) In addition, URLs (or other identifiers) of any linked-to documents included in the content or a URL (or other identifier) for the content itself may also be included. More generally, any information representative of the content, or some aspect of the content, may be included in a context vector.

At step 912, the context vector is inserted into a block of generic code implementing a contextual search interface. In one embodiment, the generic code block includes a template for an enhanced URL that is to be used for sending contextual queries to the search server, and step 912 includes inserting the context vector (or an encoded representation thereof) into this template. The generic code block may also include other code, such as code for inserting the user's query into the enhanced URL before sending it to the search server, code for displaying the contextual search interface in its active and/or inactive states, and so on. The resulting code block, including the context vector, is returned to the content developer at step 914.

FIG. 9B is a flow diagram of an alternative process 920 that may be implemented in context module 702. Process 920 begins when content to be associated with a contextual search interface is received by context module 702 (step 922). At step 924, the received content is tokenized, e.g., as described above with reference to step 904 of process 900. At step 926, any stopwords in the tokenized text, e.g., by matching tokens to stopwords in stopwords dictionary 712 and discarding any tokens that match.

At step 928, the remaining tokens are matched to terms appearing in term dictionary 706. Any token that does not match a term in term dictionary 706 is discarded.

At step 930, a term weight for each remaining token is computed. The weight may be based on the inverse of the document frequency and/or the term frequency of the token (i.e., the number of times the term appears in the received text). In one embodiment, the term weight is based on the product of the inverse document frequency and the term frequency; the weight may be resealed (e.g., linearly, logarithmically, exponentially) as desired. Other formulas for computing a term weight may be used.

At step 932, a number of tokens are selected as elements of a “term vector” based on the respective term weights. In some embodiments, the number of term vector elements is limited (e.g., to 5, 15, 25 or 50), with terms having higher term weight receiving priority. A cutoff at a minimum term weight may also be applied, with terms below the minimum weight being excluded from the term vector even if the result is a term vector with fewer than the maximum number of elements. Other selection techniques may also be used.

At step 934, the term vector is inserted as a context vector into a generic contextual search code block, and at step 936, the code block is returned to the client. These steps may be generally similar to steps 912 and 914 of process 900 described above.

Referring again to FIG. 8, at step 808 the content developer receives the code block from context module 702. At step 810, the content developer inserts the code block into the hosting Web page at the desired point, thereby adding the contextual search interface to the page.

It will be appreciated that the processes for creating contextual search interfaces described herein are illustrative and that variations and modifications are possible. Steps described as sequential may be executed in parallel, order of steps may be varied, and steps may be modified or combined. Various steps such as selection of content and insertion of the contextual search code block may be automated or performed manually. In one alternative embodiment, the search provider may provide a context processing module that can be installed and run on the content provider's system, so that information need not be sent to the search provider in order to create the context vector. In addition, in some embodiments creation of contextual search interfaces may be automated, e.g., so that a context vector is automatically updated when page content is updated. For instance, if page 400 of FIG. 4 represents a news page where the top stories are frequently changed, a process may be provided for automatically updating the context vector for one of the contextual search interfaces any time its associated story changes.

Other algorithms for generating context vectors may also be implemented. For example, some algorithms may weight terms that appear in headings, subheadings, metatags or other selected fields higher than terms in the body text. Some algorithms may also take into account non-textual content (e.g., images or media content) for which suitable content descriptors are available or can be determined. Terms in the context vector are not limited to single words; a term may also be a phrase (two or more words occurring adjacent to each other).

In some embodiments, the context vector may be created based on information other than terms found in the content. For instance, the content provider may be prompted to specify a category or other context identifier for the content, and this information may be included in the context vector. In still other embodiments, the context vector may include information about links included in the content (e.g., the URLs of such links, page titles or category information for the linked-to pages, and so on).

In some embodiments, the context vector may be included in the contextual search interface code block in an encoded form. For example, hash functions or other suitable techniques may be used to represent various tokens in the context vector. As another example, the complete context vector data might be stored in a table or database accessible to the search server, and the code block might include a key or other code that the search server can use to look up the context vector data during query processing.

B. By Users

In another embodiment, a user viewing any Web page can create a contextual search interface for that page (or for a portion thereof). For example, the search provider may provide a browser toolbar that has a “contextual search” widget enabling the user to select as context for a search query a portion of any Web page displayed in the browser window.

FIG. 10 is a flow diagram of a process 1000 for user creation of a contextual search interface. When process 1000 begins, the user is viewing a Web page using a browser (e.g., an aspect of user interface module 127 of client application 125 of FIG. 2). The user's browser is equipped with a toolbar that has a “contextual search” widget. The page being viewed might or might not include a contextual search interface supplied by the content provider. At step 1002, while viewing the page, the user selects the “contextual search” button from the toolbar, e.g., by clicking on it. In response, at step 1004, the browser prompts the user to select a portion of the displayed page as context for the search. The prompt may include, e.g., changing a mouse cursor to a shape indicative of selection, and/or displaying a text prompt.

At step 1006, the user selects part or all of the displayed page, e.g., by clicking and dragging a mouse cursor over a region of the displayed page. Selected text may be shown with highlighting (e.g., modified colors or a box drawn around the content) to provide visual feedback to the user. In some embodiments, other content selection mechanisms may be provided in addition to or instead of click-and-drag techniques. For example, a user may be able to select the entire page by pressing a predefined key, to select a paragraph by clicking while the mouse cursor is positioned anywhere in the paragraph, or to select a section by clicking while the mouse cursor is positioned in the section heading.

At step 1008, client application 125 generates a context vector from the selected content. In one embodiment, client application 125 may submit the selected content to context processing module 166 at search server 160 for context-vector generation in accordance with process 900 described above. In another embodiment, client application 125 is configured to process content locally to generate a context vector (e.g., via steps of process 900) without transmitting information to the search server. Such processing capability may be implemented, e.g., by including a context processing module as part of specialized search module 126 of client application 125 of FIG. 2.

At step 1010, the browser redisplays the current page, adding a contextual search interface at or near the selected portion of the page. In this embodiment, the newly added contextual search interface may appear initially in an active state so that the user can simply enter and submit a query without first activating the interface, or it may appear in an inactive state. Once created, a user-created contextual search interface advantageously behaves similarly to contextual search interface 304 described above; specifically, when the user enters a query through a user-created contextual-search interface, the client application submits the query and the context vector associated with the user-created contextual search interface to the search server.

It will be appreciated that process 1000 is illustrative and that variations and modifications are possible. Steps described as sequential may be executed in parallel, order of steps may be varied, and steps may be modified or combined. For instance, the user may select the content first, then activate a “contextual search” button in the search toolbar. Instead of adding a contextual search interface to the Web page, a user-created contextual search interface may be placed in the toolbar (e.g., in place of a standard non-contextual search interface) or provided in a separate pop-up window.

In other embodiments, rather than generating a context vector in advance of a query, the client application may send the selected content together with the user's query to the search server, and the search server may generate the context vector (e.g., using context processing module 166) as part of its query processing activity. This context vector may be sent back to the client application, which may cache it for subsequent reuse.

Where selected content is submitted together with a query, the query may also be used in selecting terms for the context vector. FIG. 11 is a flow diagram of a process 1100 for generating a context vector from a combination of content and a query according to an embodiment of the present invention. Process 1100 may be implemented in the embodiment of FIG. 7, with context client 704 corresponding to a browser program that communicates with context module 702.

Process 1100 begins when content and a query for a contextual search are received by context module 702 (step 1102). At step 1104, a term vector is generated from the received content, e.g., in accordance with steps 924 through 932 of process 920 (FIG. 9B) described above.

At step 1106, the received text is parsed to identify each occurrence of a term from the received query. At step 1108, a window of text surrounding each occurrence of a query term is selected. In one embodiment, each window includes a fixed number of words (e.g., 2, 3, 5, 10) preceding and following the query term. At step 1110, each selected window is matched against segment dictionary 708 (FIG. 7); a match occurs if any segment in dictionary 708 appears in the window.

At step 1112, a segment weight is computed for each matched segment. Segment weights may be defined similarly to term weights described above. At step 1114, the segments with the highest weights are chosen for a “segment vector.” As with the term vector, a minimum threshold weight may be applied, and the number of segments in the segment vector may be limited to a maximum value.

At step 1116, the segment vector is merged with the term vector generated at step 1104, creating a context vector. In one embodiment, the vectors may simply be concatenated. In another embodiment, terms from the term vector that also appear within a segment in the segment vector may be removed entirely or may have their term weights reduced. If desired, the total number of entries may be limited to some maximum number.

At step 1118, the context vector is returned to the client. In an alternative embodiment, the context vector may be forwarded, together with the received query, to a search server (e.g., search server 160 of FIG. 2) for immediate query processing.

It will be appreciated that process 1100 is illustrative and that variations and modifications are possible. Steps described as sequential may be executed in parallel, order of steps may be varied, and steps may be modified or combined. In some embodiments, the context vector may be further enhanced with information from a concept network, as described below.

In another embodiment, a user may be able to refine the context for a pre-existing contextual search interface, e.g., by selecting a portion of the accompanying text. Where such a selection is made, the context vector associated with the contextual search interface can be modified, e.g., to include only terms that appear in the selected text, thereby providing users a further degree of control over how the context is defined.

In still another embodiment, a client application might also include a module for creating contextual searches that is accessible via an icon on the user's desktop or in an operating system toolbar. Such a module may enable a user to create context vectors for performing contextual searches based on content other than Web pages, including documents open in a word processing or file viewer application, e-mail messages, instant messages, and the like. The user may activate this icon at any time, whether or not a browser is open, and may select content for creating the context vector from any document on her desktop (including any Web pages that happen to be displayed). The user-created contextual search interface for the selected content appears, e.g., in a pop-up window or dialog box located near the selected content, or in any other suitable user interface element. When the search is executed and results are returned, the client application advantageously opens a browser window for displaying the results and allowing the user to navigate to the hit pages or sites.

III. Use of Context Vectors in Query Processing

As described above, when a contextual search interface such as interface 304 of FIG. 3 is active, a user may initiate a contextual search by entering a query into text field 306 and operating submit button 308. In response, contextual information, which can aid the search server in responding to the user's query, is supplied via a context vector (e.g., context vector 400 of FIG. 4) that is associated with the contextual search interface and automatically delivered to the search server with the user's query.

A search server (e.g., search server 160 of FIG. 2) receives a contextual search query, which includes both the user's query and the context vector, and executes the search, e.g., using query response module 164. Algorithms for processing contextual search queries advantageously exploit the premise that the user's interest is likely to be related to the neighboring content; accordingly, the context vector, which represents that content, is advantageously used in generating search results. It should be noted that a user who does not want a search to be connected to surrounding content may use a different interface (e.g., a search toolbar or the search provider's Web interface) to perform a non-contextual search, and search server 160 may be configured to process both contextual and non-contextual queries.

A. Processing Algorithms for Contextual Search

Specific algorithms for processing contextual search queries will now be described. FIG. 12 is a flow diagram of one such process 1200, in which search terms provided by the user are supplemented using one or more additional terms from the context vector.

At step 1202, a contextual query, including at least one user-supplied term and an associated context vector, is received. At step 1204, one or more user keywords are extracted from the user-supplied terms, e.g., using conventional query parsing techniques, which may include detecting word boundaries, canonicalizing words (e.g., removing suffixes, correcting spelling errors or variants, and the like), eliminating words that are too common to be helpful in searches (e.g., “the,” “and”), and so on.

At step 1206, one or more context keywords are extracted from the context vector to supplement the user keywords. In some embodiments, context vectors include terms that have already been parsed and canonicalized (e.g., as described for process 900 above) and so are already suitable for use as keywords. In other embodiments, parsing and canonicalization may be performed for terms in the context vector as well. In addition, step 1206 may include determining how many and which terms from the context vector should be used as context keywords. For instance, in some embodiments, only terms having at least a minimum frequency or weight might be selected, or a limit might be placed on the number of terms that can be selected, with the most frequent or highest weighted terms being selected first. The number of context keywords selected may also depend on the number of user keywords (e.g., for queries with more user keywords, fewer context keywords might be selected). Step 1206 may also include detecting and removing from the query any context keywords that are redundant with user keywords. Redundant keywords may include exact duplicates as well as known synonyms.

At step 1208, a search is executed using a query that includes the user keywords and the context keywords. Search execution may incorporate conventional techniques for identifying Web pages that contain one or more (or, in some embodiments, all) of the keywords; such pages are referred to herein as “hits” (or “search hits”). At step 1210, the search hits are ranked based on relevance as determined by a suitable ranking algorithm. Conventional algorithms for scoring each hit page based on frequency and/or proximity of keywords in the hit page may be used, with the user's keywords and/or the contextual keywords being taken into account in the scoring. In addition, any terms from the context vector that were not selected as keywords may be used in determining page scores or rankings. Other criteria, including the number of pages linking to the hit, user evaluations and preferences related to hit pages, and/or sponsorship of various hit pages may also be considered in determining the ranking.

At step 1212, the search results are returned to the user. In one embodiment, the results are returned as a Web page displayable via the user's browser, with links to the various hit pages or sites. The results page may be displayed, e.g., by redirecting the browser from the hosting page to the results page or by opening a new browser window for the results page. Where many hits are to be returned, multiple interlinked results pages may be generated. The results page may display both the user's original query and the context keywords that were added to the search query. In some embodiments, this information is presented using an interactive form via which the user can modify her query or the context keywords (or both) and submit the modified contextual query to search server 160.

FIG. 13 is a flow diagram of an alternative process 1300 for executing contextual searches. In process 1300, the user's query terms are used without additional context keywords to generate hits, and context data is incorporated into the ranking algorithm. More specifically, at step 1302, a contextual query, including at least one user-supplied term and an associated context vector, is received. At step 1304, one or more user keywords are extracted from the user-supplied terms; this step may be similar to step 1204 of process 1200 described above. At step 1306, a search is executed using a query made up of the user keywords, generating a list of hits. Unlike process 1200, keywords based on the context vector are not used to supplement the user keywords in the search query. As described for process 1200 above, search execution may be implemented using conventional techniques.

At step 1308, context keywords are extracted from the context vector; this step may be similar to step 1206 of process 1200 described above. At step 1310, the hits are ranked using the context keywords; in some embodiments, the user keywords may also be used for ranking The ranking algorithms may be generally similar to those used in step 1210 of process 1200. At step 1312, the results are returned to the user, similarly to step 1212 of process 1200. As in process 1200, the user's query and the context keywords may be presented using an interactive form via which the user can modify her query or the context keywords (or both) and submit the modified contextual query to search server 160.

It should be noted that processes 1200 and 1300 may result in lists of hits that differ as to content and/or order of the hits. Other variations in these processes are also possible. For instance some terms from the context vector may be used as context keywords in the search query while other terms are used only for ranking the hits. In another variation, only context keywords might be used for the search while user keywords are used only for ranking the search hits.

In some embodiments, the query and context vector can be used to perform multiple searches in parallel, and the final result can be obtained by aggregating page rankings across the searches. For example, a first search might use just the user keywords with the context vector having no effect; a second search might use the user keywords to identify hits and rank or score the hits using the context keywords (e.g., in accordance with process 1300 of FIG. 13); and a third search might use the user keywords and the context keywords together (e.g., in accordance with process 1200 of FIG. 12). In this embodiment, the hits are independently ranked or scored for each search; then an aggregate rank or score for each hit is computed, e.g., by conventional techniques such as averaging the ranks or scores across the multiple searches or selecting a median rank or score for the hit. If a hit does not occur in the results for one or more of the searches, it may arbitrarily be assigned a rank or score (e.g., a low rank or score), or the aggregate rank or score for the hit might be computed using only searches that produced that hit. The list of results presented to the user in this embodiment is advantageously based on the aggregate ranks or scores of the hits.

In any event, it should be understood that page rankings based on the user keywords and/or context keywords may be further modified based on other page ranking algorithms using various metadata for the query. Examples include the use of user profile data (if the user's identity is known) for search personalization, as well as various heuristics for resolving ambiguous terms, inferring local intent, etc. In addition to the list of hits, the search results page may also include sponsored results or other content as determined by the search provider.

B. Query Processing with Enhanced Context Vectors

As described above, a context vector can be formed from selected content, e.g., by extracting and arranging terms appearing in the selected content. While the context vector is a useful indicator of the user's interest, it might not include all potentially helpful terms. For example, if the context vector includes “hotel,” the user might actually be interested in lodgings in general, or travel. Accordingly, pages related to inns, motels, or travel agencies might be of interest to the user, but if those pages do not include the term “hotel,” they might not be given prominent placement in the contextual search results. Thus, it may be desirable to enhance a context vector with additional terms that are related to terms in the context vector but do not appear in the selected content.

In some embodiments, the context vector can be enhanced by reference to a concept network. As used herein, a “concept network” includes any representation of semantic, logical, syntactic or associational relationships among various terms (words or phrases). In one such representation, each term corresponds to a node in a network graph, and the relationships correspond to edges connecting pairs of nodes. Any logical or semantic relationship can be represented as an edge, and a node may have relationships to any number of other nodes. Other representations are also possible.

Concept networks can be obtained in various ways. For example, above-referenced application Ser. No. 10/713,576 describes techniques for constructing a concept network from a number of queries submitted to a search engine. The relationships are based, e.g., on correlations between occurrences of different terms. As described therein, relationships can include associations (terms that appear together in queries), extensions (terms that appear adjacent to each other in queries with sufficient frequency), and alternatives (terms that differ incrementally in spelling and have similar associations). Other relationships are also possible; for example, as described in above-referenced application Ser. No. 10/797,614, terms can be grouped into “superunits” that represent categories.

Another example of a concept network is a knowledge base, such as the WebKB-2 project developed by Philippe Martin of Griffith University (Australia). In a knowledge base, the terms are represented as categories, and the relationships are links between categories. The relationships can include hierarchical relationships (e.g., sub-type, instance, exclusion, equivalence, membership in a larger category, etc.). WebKB-2 is designed for development through multi-user collaboration, as users define new categories and link them to existing categories.

For purposes of the present description, it is to be understood that any techniques may be used to construct or represent a concept network, provided that a lookup mechanism exists for retrieving terms from the concept network that are related to an input term; examples of suitable mechanisms are known in the art. In some embodiments of the present invention, query terms and/or context vector terms are selected as input terms, and related terms retrieved from the concept network are used to enhance the context vector prior to execution of a contextual search. The related terms may be directly or indirectly related to the input term, as desired.

FIG. 14 is a flow diagram of a process 1400 for performing a contextual search with an enhanced context vector according to an embodiment of the present invention. At step 1402, a query and context vector are received from a user, e.g., via a user interface as described above. The query generally includes at least one user-supplied query term, and the context vector includes at least one context term determined from content selected by either the user or the page creator, as described above.

At step 1404, one or more of the query terms and/or context vector terms are selected as input terms for a concept network lookup operation. In one embodiment, each query term is selected. In another embodiment, one or more context terms are selected, e.g., using a formula based on the term frequency and/or document frequency of various terms in the context vector.

At step 1406, the selected terms are used for a concept network lookup operation. Each selected term is separately provided as an input term to the lookup mechanism of the concept network, and related terms are retrieved through operation of the lookup mechanism. The lookup mechanism may return any number of related terms, and step 1406 may include selecting among the related terms. For instance, the concept network might return a list of synonyms for the input term, a list of increasingly broader categories of which the input term is a member (or type), a list of sub-categories subsumed by the input term, and so on. For purposes of a contextual search, it may be useful to select just a few of the related terms, e.g., all synonyms (if any), as well as one broader category and one sub-category. Other selections are also possible, and in some embodiments, all of the related terms might be selected.

At step 1408, the related terms are added to the context vector, thereby creating an enhanced context vector. In various embodiments, adding related terms may include: setting a term frequency to a default value; setting a term type parameter (see FIG. 4) to reflect that the retrieved term is an “enhanced” term obtained from a concept network; and/or determining a document frequency for the related term (e.g., by accessing a database or index containing document frequency data).

At step 1410, a contextual search is executed using the query and the enhanced context vector. Processes such as process 1200 or 1300 described above, or other contextual search processes, may be used. As described above, the results of the contextual search are delivered to the user.

It will be appreciated that the process described herein is illustrative and that variations and modifications are possible. Steps described as sequential may be executed in parallel, order of steps may be varied, and steps may be modified or combined. In some embodiments, enhancement of the context vector can be performed when the context vector is created, using one or more terms from the context vector as inputs to the concept network lookup mechanism.

Alternative processes for generating an enhanced context vector using a concept network may also be used. FIG. 15 is a flow diagram of a process 1500 for generating an enhanced context vector according to an embodiment of the present invention. Process 1500 may be implemented, e.g., using context module 702 of FIG. 7 communicating with a user-operated context client 704. In this embodiment, concept network 710 is generated based on a set Q of previous queries received by a search provider (e.g., at search server 160 of FIG. 2). The concept network includes “units” (words or phrases) that occurred in at least one of the queries in set Q and includes information about the units and their relationships. For example, statistical information relating to the frequency of occurrence of the unit in set Q, alone and/or in conjunction with other units, frequency of occurrence of particular pairs of units in set Q, and so on may be provided. Such a concept network may be generated in accordance with techniques disclosed elsewhere (see, e.g., above-referenced application Ser. No. 10/713,576).

At step 1502, a query and content (e.g., text) are received. At step 1504, a context vector is formed from the query and the content; step 1504 may be implemented using, e.g., process 900 of FIG. 9A, process 920 of FIG. 9B, or process 1100 of FIG. 11, or other similar processes. In one alternative embodiment, step 1502 includes receiving a query and a context vector, and step 1504 may be omitted.

At step 1506, terms (including any multi-word segments or phrases) in the context vector are matched to units in the concept network. In one embodiment, all terms of the context vector are advantageously used; in another embodiment, terms of the context vector are selected based, e.g., on a weight threshold or on some limit on the number of terms; and in yet another embodiment, query terms may be used in addition to or instead of context vector terms.

At step 1508, a “noise” parameter (η) is computed for each matched unit u. In one embodiment:

$\begin{matrix} {{{\eta(u)} = \frac{N\left\lbrack {{Q❘u} = Q} \right\rbrack}{N\left\lbrack {Q❘{u \in Q}} \right\rbrack}},} & (1) \end{matrix}$ where N[Q|u=Q] represents the number of queries in set Q for which the entire query consisted of the unit u, and N[Q|uεQ] represents the number of queries in set Q for which the unit u appeared in the query, either alone or with other terms. Thus, noise parameter η(u) represents the fraction of queries in set Q containing unit u that did not contain any other unit.

At step 1510, the unit u is added to a concept vector if noise parameter η(u) exceeds a threshold (e.g., 1-2%). These steps remove from the concept vector any context vector terms that are only rarely used as standalone queries. Each unit u added to the concept vector is assigned a concept weight, which may be, e.g., N[Q|uεQ] or some other parameter reflecting the frequency of unit u in set Q.

At step 1512, for each unit u in the concept vector, extension units related to the unit u are identified in the concept network and added to the concept vector. As noted above, an extension relationship exists where two units appear adjacent to each other in queries with sufficient frequency that the concatenation of these units is itself considered a unit (referred to herein as an “extension unit”). For instance, units “san” and “jose” might have an extension relationship, in which case the concatenation “san jose” would be an extension unit related to units “san” and “jose”. Step 1512 involves identifying extension units such as “san jose”. Note that step 1512 may be extended to identify extensions involving any number of units (e.g., “new york city”, which involves three units, could be identified).

At step 1514, other units related to any unit u in the concept vector may be added to the concept vector. For example, units related to unit u as alternatives or associations (as described above) may be added, or units related to some minimum number or fraction of units in the concept vector might be added. In some embodiments, step 1514 may be omitted.

At step 1516, the concept vector is purged. For example, if the concept vector includes two (or more) one-word units that form an extension unit, the one-word units may be removed, leaving the extension unit.

Thereafter, the concept vector is merged with the context vector formed at step 1504 to generate an enhanced context vector. More specifically, at step 1518, the concept weights (for units in the concept vector) and term weights (for terms in the context vector) are rescaled to commensurate values. This rescaling advantageously addresses any systematic bias in weight values resulting from the different origins of term weights and concept weights. For instance, term weights are generally based on document frequency across a search corpus as described above, while concept weights are generally based on frequency of occurrence across a set of queries. The two types of frequency parameters may be defined and normalized differently, and rescaling removes or reduces discrepancies in the weight values that may result from such differences. In one embodiment, the term and concept weights might each be scaled to the range 0 to 100, where 100 represents a “maximum” weight; scaling may be, e.g., linear, polynomial, or exponential as desired. In some embodiments, the concept weights are further scaled down (e.g., by a factor of 2) to reflect that concept terms were obtained from inferences from terms contained in the text, rather than directly from the text.

The enhanced context vector is then formed, starting with the context vector. At step 1520, any single-word terms in the context vector that do not match units in the concept vector are discarded from the enhanced context vector. As a consequence of step 1510, the effect of step 1520 is to remove terms that are rarely (or never) used as standalone queries and are therefore considered not likely to convey useful contextual information.

At step 1522, selected units from the concept vector are added to the enhanced context vector. The selection may be based, e.g., on the rescaled concept weights, and may include comparing the rescaled concept weights to the rescaled term weights for elements present in the context vector. For example, a unit might be added to the context vector if its resealed concept weight exceeds some predetermined threshold or exceeds the resealed term weight of some number or fraction of elements in the context vector.

It will be appreciated that process 1500 is illustrative and that variations and modifications are possible. Steps described as sequential may be executed in parallel, order of steps may be varied, and steps may be modified or combined. Concept networks may be obtained from a variety of sources, not limited to previous queries, and process 1500 may be modified to use any available data about units and their relationships.

C. User Customization of Enhanced Context Vector

In other embodiments, the user may be able to customize the enhanced context vector, e.g., while viewing results of a contextual search. For example, FIG. 16 illustrates a search results page 1600 with a user-editable context vector according to an embodiment of the present invention. Page 1600 includes conventional features of a results page, such as a list of hits at 1602, a text box 1604 for editing the query, and a “Search” button 1606 for submitting the new query.

Page 1600 also includes a context box 1608 that can be edited by the user. Context box 1608 identifies, at 1610, a Web page that provided the original context vector and also provides a list of context vector terms 1612 that were used in the query (e.g., “2004 games,” “olympics,” “greece,” etc.). Each term 1612 has an associated checkbox 1614 that the user can check or uncheck to change the context prior to executing a new search. The terms 1612 advantageously include terms from the original context vector that were used in the search as well as any enhanced terms obtained by process 1400 or a variation thereof.

After changing the selection of checked boxes and/or editing the query as desired, the user can execute a new contextual query by activating “Search” button 1606. Only terms in box 1608 that are checked would be used in the context vector for the new search.

In this embodiment, context box 1608 includes a control 1616 that allows the user to “turn off” the context vector and execute a non-contextual search. In other embodiments, the user might be able to request further enhancement of the context vector, e.g., by selecting one or more terms displayed in context box 1608 to be used as input terms for another concept network lookup operation, then activating a “get more terms” control 1618. Each of the selected terms is used for a concept network lookup operation, and an enhanced context vector including terms obtained in the lookup operation(s) would be displayed in context box 1608, with checkboxes that the user could select to use or ignore each term. By repeatedly modifying the query and/or context vector and executing contextual searches, the user can iteratively refine the search results until the desired content is found.

The results page interface shown herein is illustrative, and other page layouts and formats may be substituted.

D. Query Disambiguation Using Enhanced Context Vectors

Users of existing search engines often provide queries that include only one or two terms, and the terms may have multiple meanings (or senses). Thus, if a user enters the query “jaguar” without further contextual information, it is not clear whether the user is interested in the animal, the automobile, the football team or something else entirely. In some embodiments of the present invention, a context vector can be provided for a query that is initially non-contextual, thereby assisting in disambiguation of the query.

FIG. 17 is a flow diagram of a process 1700 for disambiguation of a query according to an embodiment of the present invention. In process 1700, the user enters a query using a non-contextual search interface. Ambiguity in the query is detected, and the user is offered a list of choices to resolve the ambiguity. Each choice has an associated context vector, and once the user has made a selection, a contextual search is performed.

More specifically, at step 1702, a non-contextual query consisting of one or more terms is received. At step 1704, it is determined whether the query is ambiguous, e.g., if its terms have multiple associated meanings. In one embodiment, one or more of the query terms is used as an input term for a lookup operation of a concept network as described above. The lookup operation advantageously indicates whether the input term has multiple meanings. For example, some concept networks (e.g., WebKB-2) include explicit definitions for terms, and the presence of multiple definitions for a term would indicate multiple meanings. Other concept networks may reflect multiple meanings in other ways, e.g., by identifying a term as a member of multiple categories.

At step 1706, if multiple meanings are not detected, then a non-contextual search is performed (step 1708), and the results are displayed to the user (step 1710). Conventional techniques for performing a non-contextual search and displaying results may be used.

If multiple meanings are detected, then at step 1714, the user is prompted to select one of the meanings. Various prompts may be used. In embodiments where the concept network provides definitions during a lookup operation, the definitions may be presented to the user. Where the concept network provides a list of categories to which the term belongs, the categories may be presented. Alternatively (or in addition), a separate listing of terms associated with each sense might be presented. Regardless of how the meanings are presented, each meaning is advantageously associated with a control element (e.g., a radio button or link element) that enables the user to select that meaning.

At step 1716, the user selects the desired meaning. At step 1718, a context vector for that meaning is defined. In some embodiments, a concept network lookup operation may be used, with the query term and/or terms from the definition as inputs; the related terms obtained via the lookup operation can be used as context vector terms. In other embodiments, context vectors for each meaning might be defined in advance of receiving a query or prompting the user to select a meaning and stored in an appropriate repository. In that case, step 1718 might involve retrieving a predefined context vector from the repository.

At step 1720, a contextual search is executed using the query originally provided by the user and the context vector defined at step 1718. The result is displayed for the user at step 1710.

It will be appreciated that the disambiguation process described herein is illustrative and that variations and modifications are possible. Steps described as sequential may be executed in parallel, order of steps may be varied, and steps may be modified or combined. In some embodiments, rather than accessing a concept network to detect ambiguity and obtain a list of meanings, a listing of ambiguous terms, alternative definitions for such terms, and a context vector for each definition might be assembled in advance, e.g., by human editors, for frequently occurring ambiguous queries.

In other embodiments, the user might also be prompted to select a context in instances where a contextual query includes an ambiguous term and the context vector does not resolve the ambiguity. For example, a user who is viewing a page about a hotel in Seattle might enter the query “jaguar” into a contextual search toolbar interface. The context vector generated in this instance might not include any terms that would select among the different senses of the word “jaguar.” Where this is the case, the user can be prompted for more information to resolve the ambiguity, and the context vector can be modified or replaced based on the user's response to the prompt.

FIG. 18 is a flow diagram of a process 1800 for detecting and resolving ambiguity in a contextual search according to an embodiment of the present invention. At step 1802, a query and associated context vector are received, e.g., via a contextual search interface as described above. At step 1804, it is determined whether the query term is ambiguous; this step may be similar to steps 1704 and 1706 of process 1700 described above. If the query term is not ambiguous, then at step 1806 a contextual search is executed using the received query and context vector.

If the query term is ambiguous, then at step 1808 it is determined whether the context vector received with the query resolves the ambiguity. In one embodiment, a context vector can be defined for each known meaning of the ambiguous term, e.g., as described above. The meaning-specific context vectors are compared to the received context vector, and if there is sufficient overlap (e.g., in number of terms or fraction of terms in common between the received context vector and one of the meaning-specific context vectors), then the received context vector adequately resolves the ambiguity. If the received context vector adequately resolves the ambiguity, a contextual search is executed at step 1806 using the received context vector and the query.

If the received context vector does not resolve the ambiguity, then at step 1810, the user is prompted to select a meaning. This step may be generally similar to step 1714 of process 1700 described above. In some embodiments, the received context vector might be offered as a “meaning” in addition to the various meanings normally associated with the query term.

At step 1812, the user's selection is received. At step 1814, the received context vector may be enhanced or replaced using a context vector corresponding to the selected meaning. (Defining context vectors corresponding to a known meaning of a term is described above.) In one embodiment, the received context vector is enhanced by the addition of terms from the context vector corresponding to the selected meaning. In another embodiment, it might be inferred that the user did not intend a contextual search, and the received context vector might be replaced by the context vector corresponding to the selected meaning. In yet another embodiment, in addition to prompting the user to select a meaning, the user might also be allowed to elect whether to use or ignore the received context vector during the search. After enhancement or replacement of the context vector, a contextual search is performed (step 1806) using the query and the enhanced or replacement context vector.

It will be appreciated that this process is also illustrative and that variations and modifications are possible. Steps described as sequential may be executed in parallel, order of steps may be varied, and steps may be modified or combined. As described above, various techniques for detecting ambiguity and for generating context vectors indicative of different meanings for a term may be employed.

IV. Contextual Search Interfaces with Augmented Content

As described above, a contextual search interface advantageously includes active and inactive states. In the inactive state, a small icon may be displayed (e.g., as shown in FIG. 5); this can reduce visual clutter on the page while still informing the user that a contextual search option is available. In the active state, a query form and submit control are displayed (e.g., as shown in FIG. 3).

In some embodiments, when the contextual search interface is active, the query form may be augmented with additional content (referred to herein as “special content”) that may be of interest to the user. In general, when a user chooses to activate an inactive contextual search icon, it can be inferred that the user is likely to be interested in content related to that context. The content augmentation feature allows such content (or links to such content) to be presented as part of an active contextual search interface and not presented (or hidden) for inactive contextual search interfaces. Special content can be selected dynamically based on the context vector of the contextual search interface that is being activated.

In one embodiment, the augmented content includes shopping-related content (referred to herein as “Shop in Context”), in which opportunities to buy products related to the content are offered to the user. For example, Web page 600 of FIG. 6, described above, includes summaries of different news stories 602, 604, 606, each with its own contextual search icon 612, 614, 616. A user may activate one of these icons, e.g., icon 612, by clicking on it, thereby causing an active contextual search interface to be displayed and “Shop in Context” content to be added to the displayed page.

FIG. 19 shows a portion of Web page 600 after contextual search icon 612 has been activated. Icon 612 has been expanded to an augmented contextual search interface 1902, which includes a search box 1904 and a submit control 1906 (labeled “Search” in this example) that operate similarly to previously described contextual search interfaces. Augmented contextual search interface 1902 also includes “Shop in Context” content 1908, which in this case provides links and text identifying sites where one can buy merchandise related to the subject of news story 602 (specifically, to the musician Bono).

The “Shop in Context” content for a contextual search interface is advantageously selected based on the context vector, so that activating a different contextual search interface on the same page will generally produce different “Shop in Context” content. For example, FIG. 19 also includes a contextual search interface 1912 associated with news story 604; interface 1912 would appear when contextual search icon 616 of FIG. 6 is activated. Contextual search interface 1912 includes a text field 1914 and a submit button 1916, as well as “Shop in Context” content 1916. Because story 604 relates to a different subject from story 602, “Shop in Context” content 1916 (which relates to Venus Williams) is different from content 1908.

In some embodiments, special content such as “Shop in Context” content is generated dynamically by sending a content request from client application 125 (FIG. 2) to content augmentation server 180 when a contextual search interface is activated by a user. This content request includes the context vector, which content augmentation server 180 uses to select appropriate special content. Content augmentation server 180 may be operated by a search provider or by another promulgator of contextual search technologies.

FIG. 20 is a flow diagram of a process 2000 for generating an augmented contextual search interface that includes special content (e.g., “Shop in Context” content). At step 2002, a hosting page, such as page 600 of FIG. 6, is displayed in the user's browser. As described above, the hosting page includes one or more contextual search interfaces, each in the inactive (icon) state. At step 2004, the user activates one of these interfaces, e.g., by clicking on it. At step 2006, a content request that includes the context vector for the newly activated interface is transmitted to content augmentation server 180.

At step 2008, content augmentation server 180 generates or selects content to be added to the hosting page based on the context vector. For example, content augmentation server 180 may access sponsored content database 162 (shown in FIG. 2), which advantageously associates specific items of sponsored content with various keywords. Content augmentation server 180 can extract keywords from the received context vector and select one or more items of sponsored content from database 162 based on the keywords. The number of items selected may be limited if desired (e.g., in FIG. 19, two items are selected for each contextual search interface). Where more than the maximum number of items match the keywords, selection among the items can be based on various criteria, e.g., the number or importance of the keywords matched by each item and/or the terms of sponsorship agreements between a provider of content augmentation server 180 and various sponsors of the content in database 162.

At step 2010, content augmentation server 180 returns the special content to client application 125, which redisplays the host page (step 2012) including the special content. Any hosting page content following the insertion point of the contextual search interface may be moved down as needed to make room for the special content.

It will be appreciated that the process described herein is illustrative and that variations and modifications are possible. Steps described as sequential may be executed in parallel, order of steps may be varied, and steps may be modified or combined. In some embodiments, the special content may be selected in advance, e.g., when the contextual search interface is created or updated, and incorporated into the source code for the hosting page so that a real-time request to a content augmentation server is not required. It is to be understood that where a hosting page includes multiple contextual search interfaces, special content can be displayed for any active interfaces without also being displayed for any inactive ones.

Special content is not limited to shopping or advertising information. Other types of special content might include links to news stories related to the content, links to the most popular Web sites related to the content, related images or media content, or any other type of content. any type of special content can be selected based on the context vector, e.g., by accessing an appropriate database using the context vector. For instance, links to related news stories might be generated by querying one or more news servers or news sites using selected terms (or all terms) from the context vector. A list of the most popular related sites can be generated, e.g., by obtaining a listing of most popular sites and identifying sites from that list that contain terms from the context vector. Related images can be located by accessing an image database.

More generally, the context vector associated with a contextual search interface can be used in a variety of ways to identify related content. Using the content augmentation systems and methods described herein, displaying of such content can be deferred until the user has indicated interest in such content by activating a contextual search interface. Thus, the amount of information related to a particular topic that is displayed on the hosting page can be made dependent on the user's expressed interest in the topic.

V. Further Embodiments

Contextual search capability and context vectors have a variety of other embodiments and applications. Some examples will now be described; it is to be understood that these examples are illustrative and not limiting of the invention.

In some embodiments, context vectors can be also be used to facilitate entry of queries by users. For example, if a user begins to enter (e.g., by typing) a query into a search toolbar interface of a client application while viewing a hosting Web page, the client application might use context vector(s) from that page to generate auto completion suggestions for the query. This can be done regardless of whether a particular contextual search interface is active or inactive. For example, if at page 600 of FIG. 6, the user typed “V-E-N” into a search toolbar interface (not shown in FIG. 6), the client application might suggest “Venus” or “Venus Williams” as the intended text. The user could then hit the Enter or Tab key (or any other designated key) to accept the suggestion or just ignore the suggestion and keep typing. Similarly, if the user begins to type a query into a contextual search interface, the context vector for that interface may be used to generate auto completion suggestions for the user.

In other embodiments, the context vector may be used to implement a “queryless” search. From an active contextual search interface (e.g., interface 304 of FIG. 3), a user may simply activate the submit button without entering any query terms. If a contextual search with no user terms is submitted, the search server (or the client application) may be configured to construct and process a query based on the context vector or on selected terms from the context vector.

In some embodiments, the search server may collect data related to contextual searches and use this data to improve the results of such searches. Data may be collected, e.g., per context vector or per hosting page. The data may include log files containing queries that were received with a particular context vector or from a particular hosting page, clickthrough statistics indicating which hits users who entered the logged queries actually investigated, explicit user ratings of hit pages, and the like. This data may be used in various ways to improve the results of contextual searches. For example, when a query comes from a particular contextual search interface, the search server might include with the search results one or more suggestions for related queries that the user might want to explore next. The related queries can be determined, e.g., based on other queries that have frequently been received with the same context vector or from the same hosting page.

As another example, clickthrough data and/or explicit ratings data associated with hits resulting from searches using a given context vector or contextual search interface may be used to refine the scoring or ranking of search hits during processing of subsequent queries that include the same context vector or that originate from the same contextual search interface. For example, hit pages or sites that have been frequently visited or highly rated by previous users having a particular context (as represented by the context vector) are relatively likely to be useful to subsequent users having the same context; such hits may have their scores or rankings adjusted upward so that they receive more prominent placement. Conversely, hits that have been generally ignored or that have received low user ratings within a particular context are less likely to be relevant and may have their scores or rankings adjusted downward.

In addition, aggregated data about queries and/or clickthroughs originating from a particular contextual search interface may be shared with the content provider responsible for the contextual search interface, preferably without identifying individual users. The content provider can use such data to gain insight into the interests and behavior of users who visit the site, which may help the content provider to improve the usefulness and popularity of the site.

Query and/or clickthrough data may also be used for content augmentation. For instance, when a user activates a contextual search interface, the special content may include a list of the most frequent queries submitted via that interface or the sites most frequently visited by previous users of that interface. These queries or sites may be presented using active links so that the user can execute one of the queries or visit a site by clicking the link.

In some embodiments, a search server (or another server) may collect data about existing contextual search interfaces and define relationships between them based on their respective context vectors. For example, a “similarity” relationship might be defined between two interfaces that have a certain fraction of context vector terms in common; a “refinement” relationship might be defined where one interface's context vector includes all of the terms of another interface's context vector plus at least one additional term. In this manner, a graph with contextual search interfaces as nodes and the relationships as edges may be defined. A representation of the graph may be used during query processing. For instance, suppose that a contextual search interface A is a refinement of a contextual search interface B. When a query is submitted via interface B, terms from the context vector of interface A might be used in processing the query. Other relationships, including indirect relationships (e.g., if A is a refinement of B and B is a refinement of C, then it can be inferred that A is a refinement of C), may also be defined and used in query processing.

In still other embodiments, a contextual search query can be submitted to any search server, and different contextual searches can be submitted to search servers controlled by different entities, e.g., by configuring the contextual search interface so that the URL for submitting queries directs them to the desired search server. For instance, if a contextual search interface relating to automobiles is created and if a specialized server (with search capability) for automobile information is available on the Web, the contextual search may be routed to that server by including an Internet address of that server in the URL. In this way, contextual searches can provide users with access to search servers that are especially suited to their contexts, without the users having to know in advance that such a server exists. The ability to automatically direct a query to an appropriate server in a context-dependent manner may further enhance the appeal of contextual searches to users.

Selective routing of contextual queries may be implemented in various ways. For instance, where contextual search interfaces are created by content developers, the content developer may construct a query URL directed to the address of any server on the Web and may enhance the query URL with a query appropriately formatted for the targeted server. Such enhanced URLs advantageously include contextual terms (e.g., a context vector) as well as user-supplied terms.

Similarly, where contextual search interfaces are generated automatically, a software module that generates such interfaces may be configured to select an appropriate search server and format for the query URL based on the context vector. It is to be understood that the selected search server need not have any organizational connection to a creator or promulgator of the interface-generating software module, provided that the software module is capable of generating code that will cause a request to be transmitted to the selected search server in a format that the selected search server is capable of processing.

Where the search query is to be directed to a specialized search server, the active state of the contextual search interface may include special content as described above. This special content may be provided by the specialized search server or by a content augmentation server that may be controlled by a different entity. The special content may include information about the search server to which the search will be directed, such as a link to the search server's Web site.

In yet another implementation, the decision as to where to direct a contextual search query might be made at query execution time. For example, all contextual search queries could be directed to a search server (e.g., search server 160 of FIG. 2), and the search server could determine, based on a combination of the user query and context vector information, whether to redirect the query to a different server for processing. In this implementation, the decision to redirect a query might be dependent in part on the user-supplied element of the query. For instance, suppose the content for a contextual search interface relates to a new album. If a user enters the query “review” via the contextual search interface, that query could be redirected to a database of music reviews, while if the user enters the query “buy” via the same interface, that query might be processed by the search server without redirecting.

In some embodiments, different contextual search queries may be directed to the same search server but limited to different portions of a search corpus. For example, a search provider may divide Web pages into a number of potentially overlapping “properties,” such as a “news” property, a “shopping” property, a “sports” property and so on. Each such property can be treated as a separate search corpus, and based on the query and the context vector, a search may be directed to any one or more of these properties. Where searches across multiple properties are performed, the property that returned a particular result may also be used as a factor in ranking the results.

Other embodiments include user personalization features allowing data specific to the user as well as the context to inform the search results. For example, the search provider may maintain a user profile for each registered user of its services. When a registered user who is logged in executes a search (contextual or otherwise), information about that search can be recorded and associated with the user. By analyzing patterns in a given user's queries, a “user vector” may be developed. During a contextual search, information from the user vector as well as the context vector may be used in performing the search and/or ranking the results. In addition, the user vector may also be used in dynamically generating augmented content when a user activates a contextual search interface as described above. Where the user who entered a query is identifiable, any user-specific information (e.g., sites or pages a user has bookmarked, explicit user ratings of sites or pages, and so on) may also be used in conjunction with a context vector to inform search results.

In even further embodiments, users may be able to create bookmarks for contextual search interfaces (or specific contextual queries) that they have found useful so that they can easily return to these interfaces. It will be appreciated that because contextual search interfaces return context-dependent results, not all such interfaces are likely to be equally useful to a particular user. When a user finds one that is useful, she may bookmark the page that contains it using conventional browser-based bookmarks or bookmarking functionality supported by a search toolbar; however, it will be appreciated that if the content of the hosting page changes, the context vector may change as well. Accordingly, some embodiments of the present invention enable the user to bookmark the contextual search itself, e.g., by saving the enhanced query URL that includes the context vector. When the user selects this boolcmark, she is prompted to enter a query, and a contextual search is executed, using the new query. Alternatively, the user may be able to save the query as part of the bookmark so that selecting the bookmark at some later time re-executes a particular contextual search regardless of the current content of the hosting page.

Users may also be able to share their bookmarked contextual searches with other users, e.g., through various trust network mechanisms. In still other embodiments, users may be able to annotate and label their bookmarked (or otherwise saved) contextual searches or interfaces.

While the invention has been described with respect to specific embodiments, one skilled in the art will recognize that numerous modifications are possible. For instance, where specific input devices (e.g., computer mouse) are referred to herein, it is to be understood that different input devices (e.g., keystrokes or voice commands) can be substituted. Similarly, clickable buttons and other graphical user interface control elements referred to herein may be replaced by any suitable alternative control elements.

The appearance of the contextual search interface in active and/or inactive states may also vary from that shown herein. For instance, the active interface may appear in the hosting page as shown in FIG. 3 or in a separate pop-up window. In addition, the look of the icon and/or the active interface elements may be varied. Such variation may be controlled by a contextual search promulgator or a content provider. As just one example, the look of the inactive icon may be varied to suggest the context; thus, a film reel might be included in an icon for entertainment-related searches, a football or baseball might be included in icons for sports-related searches, and so on. A consistent text string (e.g., “Search This” as shown in FIG. 6) or other element may be included in the icon as a further indication that the icon represents' a contextual search interface.

In another variation, the inactive state of a contextual search icon may be implemented with hidden and visible modes. For example, the contextual search icon may be hidden (i.e., not displayed on the hosting page) except when the user's mouse cursor is positioned or moved over the associated content. When the mouse cursor is so positioned, the icon becomes visible and the user may click on it to activate it. Hidden and visible modes may be implemented, e.g., using a language such as Java.

The embodiments described herein may make reference to Web sites pages, links, and other terminology specific to instances where the World Wide Web (or a subset thereof) serves as the search corpus. It should be understood that the systems and processes described herein can be adapted for use with a different search corpus (such as an electronic database or document repository) and that results may include content as well as links or references to locations where content may be found.

In addition, the invention has been described with reference to computer systems having particular hardware and software elements. It is to be understood that other systems with different combinations of hardware and/or software components could also be implemented.

Thus, although the invention has been described with respect to specific embodiments, it will be appreciated that the invention is intended to cover all modifications and equivalents within the scope of the following claims. 

1. A method for processing a query, the method comprising the computer implemented steps of: receiving a user query that includes an ambiguous query term; receiving from a first client operated by the user, in a first request that includes said user query, a user context vector; wherein the user context vector includes first context data derived from first content displayed at the first client; wherein the first content is content that was displayed by a first content presentation application at the first client, when the user query was entered by the user; wherein the user context vector includes one or more terms that are not part of the user query; identifying a plurality of meanings for the ambiguous query term; determining whether the user context vector resolves the ambiguous query term; transmitting to a user data indicating each of the plurality of meanings to the user, for selection by the user; wherein transmitting to a user data indicating each of the plurality of meanings to the user, for selection by the user, occurs in response to determining that the user context vector does not resolve the ambiguous query term; receiving a user selection of one of the plurality of meanings; generating a search result using at least the user query, a first context vector based on the selected meaning, and a list of hits obtained from searching a search corpus, wherein the first context vector includes at least one term; and transmitting the search result for presentation to the user; wherein the method is performed by one or more computing devices.
 2. The method of claim 1, wherein identifying the plurality of meanings includes: retrieving from a concept network a plurality of alternative categories to which the ambiguous query term belongs, wherein each of the alternative categories corresponds to a different one of the plurality of meanings.
 3. The method of claim 1, wherein identifying the plurality of meanings includes: retrieving from a concept network a plurality of alternative definitions for the ambiguous query term.
 4. The method of claim 1, further comprising defining the context vector by: retrieving from a concept network a plurality of terms related to the ambiguous query term, wherein each related term is related to the selected meaning of the ambiguous query term; and selecting at least one of the related terms for inclusion in the context vector.
 5. The method of claim 4, wherein the related terms include one of a synonym of the ambiguous query term, a category of which the ambiguous query term is a member, and a sub-category subsumed by the ambiguous query term.
 6. The method of claim 1, further comprising: generating the first context vector by enhancing the user context vector with at least one term related to the selected meaning.
 7. The method of claim 1, further comprising: determining the first context vector based on the selected meaning; and replacing the user context vector with the first context vector.
 8. The method of claim 1, wherein the data indicating the plurality of meanings indicates, for each of the plurality of meanings, a category or subcategory of which the ambiguous query term is a member.
 9. The method of claim 1, further comprising: receiving from a second client, in a second request that includes said user query, a second context vector wherein the second context vector includes second context data derived from second content displayed at the second client; wherein the second content is content that was displayed by a second content presentation application at the second client, when the user query was entered at the second client; wherein the second context vector includes one or more terms that are not part of the user query; determining whether the second context vector resolves the ambiguous query term; in response to determining that the second context vector resolves the ambiguous query term, searching a search corpus using the user query and the second context vector to obtain a second search result; and transmitting the second search result for presentation to the user.
 10. The method of claim 1, wherein generating the search result comprises one or both of: searching the search corpus to obtain the list of hits based on search criteria that is based, at least in part, on the first context vector; ranking the plurality of hits based, at least in part, on the first context vector.
 11. A computer-readable storage medium storing one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform: receiving a user query that includes an ambiguous query term; receiving from a first client operated by the user, in a first request that includes said user query, a user context vector; wherein the user context vector includes first context data derived from first content displayed at the first client; wherein the first content is content that was displayed by a first content presentation application at the first client, when the user query was entered by the user; wherein the user context vector includes one or more terms that are not part of the user query; identifying a plurality of meanings for the ambiguous query term; determining whether the user context vector resolves the ambiguous query term; transmitting to a user data indicating each of the plurality of meanings to the user, for selection by the user; wherein transmitting to a user data indicating each of the plurality of meanings to the user, for selection by the user, occurs in response to determining that the user context vector does not resolve the ambiguous query term; receiving a user selection of one of the plurality of meanings; generating a search result using at least the user query, a first context vector based on the selected meaning, and a list of hits obtained from searching a search corpus, wherein the first context vector includes at least one term; and transmitting the search result for presentation to the user.
 12. The computer-readable storage medium of claim 11 wherein identifying the plurality of meanings includes: retrieving from a concept network a plurality of alternative categories to which the ambiguous query term belongs, wherein each of the alternative categories corresponds to a different one of the plurality of meanings.
 13. The computer-readable storage medium of claim 11 wherein identifying the plurality of meanings includes: retrieving from a concept network a plurality of alternative definitions for the ambiguous query term.
 14. The computer-readable storage medium of claim 11 wherein the one or more sequences of instructions, when executed by the one or more processors, further cause the one or more processors to perform: retrieving from a concept network a plurality of terms related to the ambiguous query term, wherein each related term is related to the selected meaning of the ambiguous query term; and selecting at least one of the related terms for inclusion in the context vector.
 15. The computer-readable storage medium of claim 14 wherein the related terms include one of a synonym of the ambiguous query term, a category of which the ambiguous query term is a member, and a sub-category subsumed by the ambiguous query term.
 16. The computer-readable storage medium of claim 11 wherein the one or more sequences of instructions, when executed by the one or more processors, further cause the one or more processors to perform: generating the first context vector by enhancing the user context vector with at least one term related to the selected meaning.
 17. The computer-readable storage medium of claim 11 wherein the one or more sequences of instructions, when executed by the one or more processors, further cause the one or more processors to perform: determining the first context vector based on the selected meaning; and replacing the user context vector with the first context vector.
 18. The computer-readable storage medium of claim 11 wherein the data indicating the plurality of meanings indicates, for each of the plurality of meanings, a category or subcategory of which the ambiguous query term is a member.
 19. The computer-readable storage medium of claim 11 wherein the one or more sequences of instructions, when executed by the one or more processors, further cause the one or more processors to perform: receiving from a second client, in a second request that includes said user query, a second context vector wherein the second context vector includes second context data derived from second content displayed at the second client; wherein the second content is content that was displayed by a second content presentation application at the second client, when the user query was entered at the second client; wherein the second context vector includes one or more terms that are not part of the user query; determining whether the second context vector resolves the ambiguous query term; in response to determining that the second context vector resolves the ambiguous query term, searching a search corpus using the user query and the second context vector to obtain a second search result; and transmitting the second search result for presentation to the user.
 20. The computer-readable storage medium of claim 11, wherein generating the search result comprises one or both of: searching the search corpus to obtain the list of hits based on search criteria that is based, at least in part, on the first context vector; ranking the plurality of hits based, at least in part, on the first context vector. 